Formation of carbon nitride films on Si(100) substrates by electron cyclotron resonance plasma assisted vapor deposition

Abstract

We report the growth of thin carbon nitride films on Si(100) substrates at temperatures in the range of 100–700 °C using electron-beam evaporation of graphite assisted with electron cyclotron resonance (ECR) plasma generated nitrogen species. The effect of the substrate temperature, and the nitrogen flow on the composition ratio C/N, and the C—N bonding were investigated using Fourier transform infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectroscopy (RBS), and Raman spectroscopy. The FTIR spectra show that the films produced exhibit a very high visible to infrared transmittance (0.85–0.95). These spectra were dominated by amine group (NH2) with the presence of C-N stretching modes. From both RBS and XPS, the nitrogen concentration in the film was calculated and was found in the range of 24%–48%, depending on the nitrogen partial pressure in the ECR source. Raman spectrum of the high nitrogen content thin film shows a well resolved peak at 1275 cm−1 suggesting the formation of a fourfold coordinated (sp3) CN film.

Carbon nitride thin films prepared by a capacitively coupled RF plasma jet

“…There is a general agreement that the peak around 2200 cm-' (in the present spectrum at 2190 cm-') is due to carbon bond in sp state (triple bonded CN stretching mode [3,15,16,. The bands due to carbon bonded with N having sp2 and sp3 states should appear in the region 1200-1400 cm-' [6,15,20,21] and are present in the spectrum as shoulders of the large double peaked absorption band around 1600 cm ' . This band is caused by the superposition of NH, bands at 1550 cm-' and 1660 cm-' (symmetric and asymmetric bending modes) and the C = C band at 1630 cm-' [3,6].…”

“…The bands due to carbon bonded with N having sp2 and sp3 states should appear in the region 1200-1400 cm-' [6,15,20,21] and are present in the spectrum as shoulders of the large double peaked absorption band around 1600 cm ' . This band is caused by the superposition of NH, bands at 1550 cm-' and 1660 cm-' (symmetric and asymmetric bending modes) and the C = C band at 1630 cm-' [3,6]. In order to establish the contribution of different bands to the film absorption in the region 1200-1500 cm-' the deconvolution of absorption for this spectral range has been performed.…”

“…Two peaks situated at 1225 cm-' and 1400 cm-' are assigned as the C-N stretching mode in [6]. In Ref.…”

Nitrogen incorporation during metal organic chemical vapor deposition of ZnO films using a remote Ar∕N2 plasma

“…This was confirmed by infrared spectroscopy, which showed the presence of an absorption line at 2203 cm −1 , associated with the nitrile bond ͑-C w N͒ stretching vibration. 17,18 As shown in Fig. 1, its concentration increases with nitrogen flow.…”

Depósito de capas de nitruro de carbono mediante ablación láser

“…Así, se puede deducir la presencia de nitrógeno enlazado al carbono en diferentes configuraciones que se asignan a C-N (1.300-1.500 cnr 1 ), C=N (1.500-1.750 cnr 1 ) y CN (2.150-2.300 cnr 1 ), y también la incorporación de hidrógeno enlazado a carbono (2.800-3.000 cnr 1 ) y a nitrógeno (NH X en la banda de 3.200 a 3.350 cnr 1 y en 1.550 cnr 1 ). No obstante, las frecuencias de las bandas de absorción infrarroja para los CN X no están todavía definitivamente identificadas en la literatura (12)(13)(14). Cabe resaltar que la utilización de un blanco de guanazol repercute en una mayor eficiencia en la incorporación de nitrógeno y en una mayor diversidad de enlaces presentes en las capas, siendo de especial interés la formación de enlaces C-N. Las diferencias más relevantes que se observan en las figuras 3 y 4 son justificables atendiendo a los mecanismos del proceso de depósito.…”